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1.
Gates Open Res ; 7: 50, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37868333

RESUMO

Background: The Masimo Total Hemoglobin SpHb® is a continuous and non-invasive handheld device to measure hemoglobin levels. Previous research has found that SpHb is able to accurately detect hemoglobin levels in adult patients with a similar degree of bias and standard deviation to point-of-care invasive method measurements. Generally, limited clinical evidence, lack of validation of Masimo at higher than and lower than hemoglobin threshold values, and scientific consensus supporting the use of Masimo for accurate hemoglobin testing for the diagnosis of anemia during pregnancy calls for further research. Methods and analysis: The proposed prospective cohort will be nested within the ongoing Pregnancy Risk and Infant Surveillance and Measurement Alliance (PRISMA) Maternal and Newborn Health (MNH) study. Three study sites (located in Zambia, Kenya, and Pakistan) will participate and collect hemoglobin data at five time points (<20 weeks, 20 weeks, 28 weeks, 36 weeks' gestation, and six weeks postpartum). We will measure hemoglobin using a venous blood sample via hematology auto-analyzer complete blood count (gold standard) and the non-invasive device. The primary objective is to assess agreement between Masimo total hemoglobin and complete blood count and on a continuous scale using Intraclass Correlation Coefficient and Bland-Altman Analysis. The second objective is to assess agreement between the two measures on a binary scale using Positive Percentage Agreement and Negative Percentage Agreement, Cohen's Kappa, and McNemar Test. On an ordinal scale, agreement will be measured using Weighted Cohen's Kappa and Harrel's Concordance Index. Lastly, we will assess factors that might affect the accuracy of Masimo total hemoglobin using linear mixed models. Conclusions: The primary aim of this study is to assess the validity of the non-invasive Masimo device compared to the gold standard method of invasive hemoglobin measurements during pregnancy and postpartum periods for the diagnosis of anemia.


Assuntos
Anemia , Saúde do Lactente , Adulto , Feminino , Humanos , Lactente , Recém-Nascido , Gravidez , Contagem de Células Sanguíneas , Hemoglobinas/análise , Estudos Prospectivos , Estudos Observacionais como Assunto
2.
Environ Sci Technol ; 56(2): 1267-1277, 2022 01 18.
Artigo em Inglês | MEDLINE | ID: mdl-34981927

RESUMO

Polymers reinforced with virgin carbon fibers (VCF) are being used to make spar caps of wind turbine (WT) blades and polymers with glass fibers (GF) to make skins of the blade components. Here, we assess the life cycle environmental performance of the hybrid blades with spar caps based on VCF and the shells and shear webs based on RCF (recycled CF) composites (RCF-hybrid). The production of the WT blades and associated reinforced polymers is assumed to occur in Sweden, with their uses and end-of-life management in the European region. The functional unit is equivalent to three blades in an offshore WT with the market incumbent blades solely based on the GF composite or the hybrid option. The RCF-hybrid blades offer 12-89% better environmental performance in nine out of 10 impact categories and 6-26% better in six out of 10 impact categories. The RCF-hybrid blades exhibit optimum environmental performance when the VCF manufacturing facilities are equipped with pollution abatement systems including regenerative thermal oxidizers to reduce ammonia and hydrogen cyanide emissions; spar caps are made using VCF epoxy composites through pultrusion and resin infusion molding, and the blade scrap is mechanically recycled at the end of life. The energy and carbon payback times for the RCF-hybrid blades were found to be 5-13% lower than those of the market incumbents.


Assuntos
Carbono , Reciclagem , Fibra de Carbono , Suécia
3.
Physiol Meas ; 42(8)2021 08 27.
Artigo em Inglês | MEDLINE | ID: mdl-34384069

RESUMO

Objective. The measurement of the static compliance of the respiratory system (Cstat) during mechanical ventilation requires zero end-inspiratory flow. An inspiratory pause maneuver is needed if the zero end-inspiratory flow condition cannot be satisfied under normal ventilation.Approach. We propose a method to measure the quasi-static respiratory compliance (Cqstat) under pressure control ventilation mode without the inspiratory pause maneuver. First, a screening strategy was applied to filter out breaths affected strongly by spontaneous breathing efforts or artifacts. Then, we performed a virtual extrapolation of the flow-time waveform when the end-inspiratory flow was not zero, to allow for the calculation ofCqstatfor each kept cycle. Finally, the outputCqstatwas obtained as the average of the smallest 40Cqstatmeasurements. The proposed method was validated against the gold standardCstatmeasured from real clinical settings and compared with two reported algorithms. The gold standardCstatwas obtained by applying an end-inspiratory pause maneuver in the volume-control ventilation mode.Main results. Sixty-nine measurements from 36 patients were analyzed. The Bland-Altman analysis showed that the bias of agreement forCqstatversus the gold standard measurement was -0.267 ml/cmH2O (95% limits of agreement was -4.279 to 4.844 ml/cmH2O). The linear regression analysis indicated a strong correlation (R2 = 0.90) between theCqstatand gold standard.Significance. The results showed that theCqstatcan be accurately estimated from continuous ventilator waveforms, including spontaneous breathing without an inspiratory pause maneuver. This method promises to provide continuous measurements compliant with mechanical ventilation.


Assuntos
Respiração Artificial , Sistema Respiratório , Humanos , Ventiladores Mecânicos
4.
Environ Health Prev Med ; 26(1): 4, 2021 Jan 08.
Artigo em Inglês | MEDLINE | ID: mdl-33419405

RESUMO

BACKGROUND: Severe hand-foot-and-mouth disease (HFMD) is a life-threatening contagious disease among young children and infants. Although enterovirus A71 has been well acknowledged to be the dominant cause of severe HFMD, there still remain other unidentified risk factors for severe HFMD. Previous studies mainly focused on identifying the individual-level risk factors from a clinical perspective, while rare studies aimed to clarify the association between regional-level risk factors and severe HFMD, which may be more important from a public health perspective. METHODS: We retrieved the clinical HFMD counts between 2008 and 2014 from the Chinese Center for Disease Control and Prevention, which were used to calculated the case-severity rate in 143 prefectural-level cities in mainland China. For each of those 143 cities, we further obtained city-specific characteristics from the China City Statistical Yearbook (social and economic variables) and the national meteorological monitoring system (meteorological variables). A Poisson regression model was then used to estimate the associations between city-specific characteristics (reduced by the principal component analysis to avoid multicollinearity) and the case-severity rate of HFMD. The above analysis was further stratified by age and gender to examine potential modifying effects and vulnerable sub-populations. RESULTS: We found that the case-severity rate of HFMD varied dramatically between cities, ranging from 0 to 8.09%. Cities with high case-severity rates were mainly clustered in Central China. By relating the case-severity rate to city-specific characteristics, we found that both the principal component characterized by a high level of social and economic development (RR = 0.823, 95%CI 0.739, 0.916) and another that characterized by warm and humid climate (RR = 0.771, 95%CI 0.619, 0.960) were negatively associated with the case-severity rate of HFMD. These estimations were consistent across age and gender sub-populations. CONCLUSION: Except for the type of infected pathogen, the case-severity rate of HFMD was closely related to city development and meteorological factor. These findings suggest that social and environmental factors may also play an important role in the progress of severe HFMD.


Assuntos
Doença de Mão, Pé e Boca/epidemiologia , Adolescente , Criança , Pré-Escolar , China/epidemiologia , Cidades/epidemiologia , Feminino , Doença de Mão, Pé e Boca/virologia , Humanos , Incidência , Lactente , Recém-Nascido , Masculino , Fatores de Risco
5.
BMC Infect Dis ; 18(1): 534, 2018 Oct 26.
Artigo em Inglês | MEDLINE | ID: mdl-30367605

RESUMO

BACKGROUND: A population-based study of Chlamydia trachomatis (CT) infections is essential in designing a specific control program; however, no large investigation of CT infections among the general population in mainland China has been conducted since 2000. We aimed to determine the prevalence, risk factors, and associated medical costs of CT among residents, 18-49 years of age, in Shandong, China. METHODS: From May to August 2016, a multistage probability sampling survey involving 8074 individuals was distributed. Data were collected via face-to-face interviews, followed by self-administered questionnaire surveys. First-void urines were collected and tested for CT and Neisseria gonorrhoeae (NG) using nucleic acid amplification. RESULTS: The weighted prevalence of CT infection was 2.3% (95% confidence interval [CI], 1.5-3.2) in females and 2.7% (1.6-3.8) in males. Women, 30-34 years of age, had the highest prevalence of CT infections (3.5%, 2.6-4.4), while the highest prevalence of CT infections in males was in those 18-24 years of age (4.3%, 0.0-8.8). Neisseria gonorrhoeae infection had a prevalence of 0.1% (0.0-0.3) in women and 0.03% (0.0-0.1) in men. Risk factors for CT infections among females included being unmarried, divorced, or widowed (odds ratio [OR], 95% CI 3.57, 1.54-8.24) and having two or more lifetime sex partners (3.72, 1.14-12.16). Among males, first intercourse before 20 years of age (1.83, 1.10-3.02) and having two or more lifetime sex partners (1.85, 1.14-3.02) were associated with CT infections. The estimated lifetime cost of CT infections in patients 18-49 years of age in Shandong was 273 million (range, 172-374 million) China Renminbi in 2016. CONCLUSIONS: This study demonstrated a high burden of CT infections among females < 35 years of age and males < 25 years of age in Shandong. Thus, a CT infection control program should focus on this population, as well as others with identified risk factors.


Assuntos
Infecções por Chlamydia/epidemiologia , Chlamydia trachomatis/isolamento & purificação , Gonorreia/epidemiologia , Neisseria gonorrhoeae/isolamento & purificação , Adolescente , Adulto , Fatores Etários , China/epidemiologia , Infecções por Chlamydia/economia , Infecções por Chlamydia/urina , Custos e Análise de Custo , Estudos Transversais , Feminino , Gonorreia/economia , Gonorreia/urina , Humanos , Masculino , Pessoa de Meia-Idade , Técnicas de Amplificação de Ácido Nucleico , Prevalência , Fatores de Risco , Fatores Sexuais , Parceiros Sexuais , Inquéritos e Questionários , Adulto Jovem
6.
Stat Med ; 36(22): 3583-3595, 2017 Sep 30.
Artigo em Inglês | MEDLINE | ID: mdl-28660629

RESUMO

For cost-effectiveness and efficiency, many large-scale general-purpose cohort studies are being assembled within large health-care providers who use electronic health records. Two key features of such data are that incident disease is interval-censored between irregular visits and there can be pre-existing (prevalent) disease. Because prevalent disease is not always immediately diagnosed, some disease diagnosed at later visits are actually undiagnosed prevalent disease. We consider prevalent disease as a point mass at time zero for clinical applications where there is no interest in time of prevalent disease onset. We demonstrate that the naive Kaplan-Meier cumulative risk estimator underestimates risks at early time points and overestimates later risks. We propose a general family of mixture models for undiagnosed prevalent disease and interval-censored incident disease that we call prevalence-incidence models. Parameters for parametric prevalence-incidence models, such as the logistic regression and Weibull survival (logistic-Weibull) model, are estimated by direct likelihood maximization or by EM algorithm. Non-parametric methods are proposed to calculate cumulative risks for cases without covariates. We compare naive Kaplan-Meier, logistic-Weibull, and non-parametric estimates of cumulative risk in the cervical cancer screening program at Kaiser Permanente Northern California. Kaplan-Meier provided poor estimates while the logistic-Weibull model was a close fit to the non-parametric. Our findings support our use of logistic-Weibull models to develop the risk estimates that underlie current US risk-based cervical cancer screening guidelines. Published 2017. This article has been contributed to by US Government employees and their work is in the public domain in the USA.


Assuntos
Algoritmos , Incidência , Modelos Logísticos , Prevalência , Estatísticas não Paramétricas , Análise de Sobrevida , Adulto , Idoso , California/epidemiologia , Estudos de Coortes , Análise Custo-Benefício , Registros Eletrônicos de Saúde , Feminino , Humanos , Pessoa de Meia-Idade , Teste de Papanicolaou , Neoplasias do Colo do Útero/diagnóstico , Neoplasias do Colo do Útero/epidemiologia
7.
Comput Math Methods Med ; 2012: 608637, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-23091561

RESUMO

INTRODUCTION: Heart failure (HF) is a common and potentially fatal condition. Cardiovascular research has focused on medical therapy for HF. Theoretical modelling could enable simulation and evaluation of the effectiveness of medications. Furthermore, the models could also help predict patients' cardiac response to the treatment which will be valuable for clinical decision-making. METHODS: This study presents a fast parameters estimation algorithm for constructing a cardiovascular model for medicine evaluation. The outcome of HF treatment is assessed by hemodynamic parameters and a comprehensive index furnished by the model. Angiotensin-converting enzyme inhibitors (ACEIs) were used as a model drug in this study. RESULTS: Our simulation results showed different treatment responses to enalapril and lisinopril, which are both ACEI drugs. A dose-effect was also observed in the model simulation. CONCLUSIONS: Our results agreed well with the findings from clinical trials and previous literature, suggesting the validity of the model.


Assuntos
Insuficiência Cardíaca/tratamento farmacológico , Algoritmos , Inibidores da Enzima Conversora de Angiotensina/farmacologia , Pressão Sanguínea , Cardiologia/métodos , Simulação por Computador , Tomada de Decisões , Sistemas de Apoio a Decisões Clínicas , Enalapril/farmacologia , Hemodinâmica , Humanos , Lisinopril/farmacologia , Modelos Estatísticos , Modelos Teóricos , Análise de Regressão , Processamento de Sinais Assistido por Computador , Falha de Tratamento , Resultado do Tratamento , Resistência Vascular
8.
Health Serv Res ; 44(5 Pt 1): 1585-602, 2009 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-19555398

RESUMO

OBJECTIVE: To characterize the influence of dialysis facilities and nephrologists on resource use and patient outcomes in the dialysis population and to illustrate how such information can be used to inform payment system design. DATA SOURCES: Medicare claims for all hemodialysis patients for whom Medicare was the primary payer in 2004, combined with the Medicare Enrollment Database and the CMS Medical Evidence Form (CMS Form 2728), which is completed at onset of renal replacement therapy. STUDY DESIGN: Resource use (mainly drugs and laboratory tests) per dialysis session and two clinical outcomes (achieving targets for anemia management and dose of dialysis) were modeled at the patient level with random effects for nephrologist and dialysis facility, controlling for patient characteristics. RESULTS: For each measure, both the physician and the facility had significant effects. However, facilities were more influential than physicians, as measured by the standard deviation of the random effects. CONCLUSIONS: The success of tools such as P4P and provider profiling relies upon the identification of providers most able to enhance efficiency and quality. This paper demonstrates a method for determining the extent to which variation in health care costs and quality of care can be attributed to physicians and institutional providers. Because variation in quality and cost attributable to facilities is consistently larger than that attributable to physicians, if provider profiling or financial incentives are targeted to only one type of provider, the facility appears to be the appropriate locus.


Assuntos
Instituições de Assistência Ambulatorial/economia , Medicare/economia , Planos de Incentivos Médicos/organização & administração , Diálise Renal/economia , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Instituições de Assistência Ambulatorial/organização & administração , Eficiência Organizacional , Planos de Pagamento por Serviço Prestado , Feminino , Gastos em Saúde , Pesquisa sobre Serviços de Saúde , Humanos , Masculino , Medicare/organização & administração , Pessoa de Meia-Idade , Planos de Incentivos Médicos/economia , Qualidade da Assistência à Saúde/organização & administração , Risco Ajustado , Fatores Socioeconômicos , Resultado do Tratamento , Estados Unidos , Adulto Jovem
9.
Med Care ; 46(2): 120-6, 2008 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-18219239

RESUMO

BACKGROUND: In developing "pay-for-performance" and capitation systems that provide incentives for improving the quality and efficiency of care, policymakers need to determine which healthcare providers to evaluate and reward. OBJECTIVES: This study demonstrates methods for determining and understanding the relative contributions of facilities and physicians to the quality and cost of care. Specifically, this study distinguishes levels of variation in resource utilization (RU), based on research to support the development of an expanded Medicare dialysis prospective payment system. RESEARCH DESIGN: Mixed models were used to estimate the variation in RU across institutional providers, physicians, patients, and months (within patients), after adjusting for case-mix. SUBJECTS: The study includes 10,367 Medicare hemodialysis patients treated in a 4.2% stratified random sample of dialysis facilities in 2003. MEASURES: Monthly RU was measured by the average Medicare allowable charge per dialysis session for separately billable dialysis-related services (mainly injectable medications and laboratory tests) from Medicare claims. RESULTS: There was financially significant variation in RU across institutional providers and to a lesser degree across physicians, after adjusting for differences in case-mix. The remaining variation in RU reflects unexplained differences across patients that persist over time and transitory fluctuations for individual patients. CONCLUSIONS: The greater variation in RU occurring across dialysis facilities than across physicians is consistent with targeting payments to facilities, but alignment of incentives between facilities and physicians remains an important goal. Similar analytic methods may be useful in designing payment policies that reward providers for improving the quality of care.


Assuntos
Instituições de Assistência Ambulatorial/economia , Medicare Part B/normas , Planos de Incentivos Médicos , Garantia da Qualidade dos Cuidados de Saúde/economia , Reembolso de Incentivo , Diálise Renal/economia , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Instituições de Assistência Ambulatorial/normas , Grupos Diagnósticos Relacionados , Recursos em Saúde/estatística & dados numéricos , Humanos , Medicare Part B/economia , Pessoa de Meia-Idade , Modelos Econométricos , Sistema de Pagamento Prospectivo , Diálise Renal/normas , Risco Ajustado , Estados Unidos
10.
J Am Soc Nephrol ; 18(9): 2565-74, 2007 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-17675667

RESUMO

Medicare is considering an expansion of the bundle of dialysis-related services to be paid on a prospective basis. Exploratory models were developed to assess the potential limitations of case-mix adjustment for such an expansion. A broad set of patient characteristics explained 11.8% of the variation in Medicare allowable charges per dialysis session. Although adding recent hematocrit values or prior health care utilization to the model did increase explanatory power, it could also create adverse incentives. Projected gains or losses relative to prevailing fee-for-service payments, assuming no change in practice patterns, were significant for some individual providers. However, systematic gains or losses for different classes of providers were modest.


Assuntos
Custos de Cuidados de Saúde , Medicare , Sistema de Pagamento Prospectivo , Diálise Renal/economia , Risco Ajustado , Adulto , Idoso , Idoso de 80 Anos ou mais , Feminino , Serviços de Saúde/estatística & dados numéricos , Hematócrito , Humanos , Masculino , Pessoa de Meia-Idade , Modelos Estatísticos , Estados Unidos
11.
Yi Chuan ; 29(5): 643-8, 2007 May.
Artigo em Chinês | MEDLINE | ID: mdl-17548337

RESUMO

Genetic co-adaptability of colony gene bank is formed in the process of system evolvement, and it is a part of the attribute of gene bank, just as the gene frequency of every locus. With the genetic co-adaptability of loci combination under the condition of genetic disequilibrium, the genesis evolution and the system status of colony could be analyzed; through the study of genetic co-adaptability, the veracity of the economy character mark could be improved. We summarized about the concept, the basic and the actuality of genetic co-adaptability.


Assuntos
Adaptação Biológica/genética , Evolução Molecular , Desequilíbrio de Ligação , Modelos Genéticos , Animais , Humanos , Método de Monte Carlo
12.
Am J Kidney Dis ; 47(4): 666-71, 2006 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-16564944

RESUMO

In April 2005, Medicare began adjusting payments to dialysis providers for composite-rate services for a limited set of patient characteristics, including age, body surface area, and low body mass index. We present analyses intended to help the end-stage renal disease community understand the empirical reasons behind the new composite-rate basic case-mix adjustment. The U-shaped relationship between age and composite-rate cost that is reflected in the basic case-mix adjustment has generated significant discussion within the end-stage renal disease community. Whereas greater costs among older patients are consistent with conventional wisdom, greater costs among younger patients are caused in part by more skipped sessions and a greater incidence of certain costly comorbidities. Longer treatment times for patients with a greater body surface area combined with the largely fixed cost structure of dialysis facilities explains much of the greater cost for larger patients. The basic case-mix adjustment reflects an initial and partial adjustment for the cost of providing composite-rate services.


Assuntos
Falência Renal Crônica/economia , Falência Renal Crônica/terapia , Diálise Renal/economia , Risco Ajustado , Adulto , Idoso , Idoso de 80 Anos ou mais , Custos e Análise de Custo , Feminino , Humanos , Masculino , Medicare , Pessoa de Meia-Idade , Estados Unidos
13.
Yi Chuan ; 26(5): 625-30, 2004 Sep.
Artigo em Chinês | MEDLINE | ID: mdl-15640075

RESUMO

The genetic relationships between economic traits and genetic markers were studied in 147 goats including Chaidamu goat (CS), Chaidamu Cashmere goat (CRS) and Liaoning Cashmere goat (LRS) in Qinghai province, China. CRS was the population of CSxLRS crossbred. The results showed as follows: the selection reaction of these blood protein polymorphisic loci were great, such as EsD, LAP and P(A-3); and EsD2-2, LAPBB and PA-32-2 were the superior marker genotypes on body weight ,Cashmere yield and Cashmere fineness respectively by Least Square method. The interaction between marker genotypes at double loci was found frequently, and their ratio between interaction variance component and genetic variance was higher. With the method of marker assisted prediction( MAP), some interaction effect could be used effectively in the crossbreed population. On the aspect of random amplified polymorphic DNA (RAPD), the number of the superior RAPD marker bands were 11 on body weight trait, 9 and 6 RAPD marker bands on Cashmere yield and Cashmere fineness. For multi-goal traits, CY0818/A0 type and OPW19/C1 type were superior RAPD markers of body weight and Cashmere yield, CY0818/G1 type was superior one of body weight and Cashmere fineness.


Assuntos
Cruzamento/economia , Marcadores Genéticos , Cabras/genética , Característica Quantitativa Herdável , Seleção Genética , Animais , Peso Corporal/genética , China , Genótipo , Cabras/classificação , Leucil Aminopeptidase/genética , Pré-Albumina/genética , Tioléster Hidrolases/genética , Lã/economia
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